main.c

   1 /*
   2  * uhttpd - Tiny single-threaded httpd
   3  *
   4  *   Copyright (C) 2010-2012 Jo-Philipp Wich <xm@subsignal.org>
   5  *   Copyright (C) 2012 Felix Fietkau <nbd@openwrt.org>
   6  *
   7  *  Licensed under the Apache License, Version 2.0 (the "License");
   8  *  you may not use this file except in compliance with the License.
   9  *  You may obtain a copy of the License at
  10  *
  11  *      http://www.apache.org/licenses/LICENSE-2.0
  12  *
  13  *  Unless required by applicable law or agreed to in writing, software
  14  *  distributed under the License is distributed on an "AS IS" BASIS,
  15  *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  16  *  See the License for the specific language governing permissions and
  17  *  limitations under the License.
  18  */
  19
  20 #define _BSD_SOURCE
  21 #define _GNU_SOURCE
  22 #define _XOPEN_SOURCE   700
  23 #include <sys/types.h>
  24 #include <sys/socket.h>
  25 #include <netinet/in.h>
  26
  27 #include <getopt.h>
  28 #include <errno.h>
  29 #include <netdb.h>
  30 #include <signal.h>
  31
  32 #include <libubox/usock.h>
  33
  34 #include "uhttpd.h"
  35 #include "tls.h"
  36
  37 char uh_buf[4096];
  38
  39 static int run_server(void)
  40 {
  41         uloop_init();
  42         uh_setup_listeners();
  43         uh_plugin_post_init();
  44         uloop_run();
  45
  46         return 0;
  47 }
  48
  49 static void uh_config_parse(void)
  50 {
  51         const char *path = conf.file;
  52         FILE *c;
  53         char line[512];
  54         char *col1;
  55         char *col2;
  56         char *eol;
  57
  58         if (!path)
  59                 path = "/etc/httpd.conf";
  60
  61         c = fopen(path, "r");
  62         if (!c)
  63                 return;
  64
  65         memset(line, 0, sizeof(line));
  66
  67         while (fgets(line, sizeof(line) - 1, c)) {
  68                 if ((line[0] == '/') && (strchr(line, ':') != NULL)) {
  69                         if (!(col1 = strchr(line, ':')) || (*col1++ = 0) ||
  70                                 !(col2 = strchr(col1, ':')) || (*col2++ = 0) ||
  71                                 !(eol = strchr(col2, '\n')) || (*eol++  = 0))
  72                                 continue;
  73
  74                         uh_auth_add(line, col1, col2);
  75                 } else if (!strncmp(line, "I:", 2)) {
  76                         if (!(col1 = strchr(line, ':')) || (*col1++ = 0) ||
  77                                 !(eol = strchr(col1, '\n')) || (*eol++  = 0))
  78                                 continue;
  79
  80                         uh_index_add(strdup(col1));
  81                 } else if (!strncmp(line, "E404:", 5)) {
  82                         if (!(col1 = strchr(line, ':')) || (*col1++ = 0) ||
  83                                 !(eol = strchr(col1, '\n')) || (*eol++  = 0))
  84                                 continue;
  85
  86                         conf.error_handler = strdup(col1);
  87                 }
  88                 else if ((line[0] == '*') && (strchr(line, ':') != NULL)) {
  89                         if (!(col1 = strchr(line, '*')) || (*col1++ = 0) ||
  90                                 !(col2 = strchr(col1, ':')) || (*col2++ = 0) ||
  91                                 !(eol = strchr(col2, '\n')) || (*eol++  = 0))
  92                                 continue;
  93
  94                         uh_interpreter_add(col1, col2);
  95                 }
  96         }
  97
  98         fclose(c);
  99 }
 100
 101 static int add_listener_arg(char *arg, bool tls)
 102 {
 103         char *host = NULL;
 104         char *port = arg;
 105         char *s;
 106
 107         s = strrchr(arg, ':');
 108         if (s) {
 109                 host = arg;
 110                 port = s + 1;
 111                 *s = 0;
 112         }
 113
 114         return uh_socket_bind(host, port, tls);
 115 }
 116
 117 static int usage(const char *name)
 118 {
 119         fprintf(stderr,
 120                 "Usage: %s -p [addr:]port -h docroot\n"
 121                 "       -f              Do not fork to background\n"
 122                 "       -c file         Configuration file, default is '/etc/httpd.conf'\n"
 123                 "       -p [addr:]port  Bind to specified address and port, multiple allowed\n"
 124 #ifdef HAVE_TLS
 125                 "       -s [addr:]port  Like -p but provide HTTPS on this port\n"
 126                 "       -C file         ASN.1 server certificate file\n"
 127                 "       -K file         ASN.1 server private key file\n"
 128 #endif
 129                 "       -h directory    Specify the document root, default is '.'\n"
 130                 "       -E string       Use given virtual URL as 404 error handler\n"
 131                 "       -I string       Use given filename as index for directories, multiple allowed\n"
 132                 "       -S              Do not follow symbolic links outside of the docroot\n"
 133                 "       -D              Do not allow directory listings, send 403 instead\n"
 134                 "       -R              Enable RFC1918 filter\n"
 135                 "       -n count        Maximum allowed number of concurrent requests\n"
 136 #ifdef HAVE_LUA
 137                 "       -l string       URL prefix for Lua handler, default is '/lua'\n"
 138                 "       -L file         Lua handler script, omit to disable Lua\n"
 139 #endif
 140 #ifdef HAVE_UBUS
 141                 "       -u string       URL prefix for HTTP/JSON handler\n"
 142                 "       -U file         Override ubus socket path\n"
 143 #endif
 144                 "       -x string       URL prefix for CGI handler, default is '/cgi-bin'\n"
 145                 "       -i .ext=path    Use interpreter at path for files with the given extension\n"
 146                 "       -t seconds      CGI, Lua and UBUS script timeout in seconds, default is 60\n"
 147                 "       -T seconds      Network timeout in seconds, default is 30\n"
 148                 "       -k seconds              HTTP keepalive timeout\n"
 149                 "       -d string       URL decode given string\n"
 150                 "       -r string       Specify basic auth realm\n"
 151                 "       -m string       MD5 crypt given string\n"
 152                 "\n", name
 153         );
 154         return 1;
 155 }
 156
 157 static void init_defaults(void)
 158 {
 159         conf.script_timeout = 60;
 160         conf.network_timeout = 30;
 161         conf.http_keepalive = 20;
 162         conf.max_requests = 3;
 163         conf.realm = "Protected Area";
 164         conf.cgi_prefix = "/cgi-bin";
 165         conf.cgi_path = "/sbin:/usr/sbin:/bin:/usr/bin";
 166
 167         uh_index_add("index.html");
 168         uh_index_add("index.htm");
 169         uh_index_add("default.html");
 170         uh_index_add("default.htm");
 171 }
 172
 173 static void fixup_prefix(char *str)
 174 {
 175         int len;
 176
 177         if (!str || !str[0])
 178                 return;
 179
 180         len = strlen(str) - 1;
 181
 182         while (len > 0 && str[len] == '/')
 183                 len--;
 184
 185         str[len + 1] = 0;
 186 }
 187
 188 int main(int argc, char **argv)
 189 {
 190         const char *tls_key = NULL, *tls_crt = NULL;
 191         bool nofork = false;
 192         char *port;
 193         int opt, ch;
 194         int cur_fd;
 195         int bound = 0;
 196         int n_tls = 0;
 197
 198         BUILD_BUG_ON(sizeof(uh_buf) < PATH_MAX);
 199
 200         uh_dispatch_add(&cgi_dispatch);
 201         init_defaults();
 202         signal(SIGPIPE, SIG_IGN);
 203
 204         while ((ch = getopt(argc, argv, "fSDRC:K:E:I:p:s:h:c:l:L:d:r:m:n:x:i:t:k:T:A:u:U:")) != -1) {
 205                 bool tls = false;
 206
 207                 switch(ch) {
 208                 case 's':
 209                         n_tls++;
 210                         tls = true;
 211                         /* fall through */
 212                 case 'p':
 213                         bound += add_listener_arg(optarg, tls);
 214                         break;
 215
 216                 case 'h':
 217                         if (!realpath(optarg, uh_buf)) {
 218                                 fprintf(stderr, "Error: Invalid directory %s: %s\n",
 219                                                 optarg, strerror(errno));
 220                                 exit(1);
 221                         }
 222                         conf.docroot = strdup(uh_buf);
 223                         break;
 224
 225                 case 'E':
 226                         if (optarg[0] != '/') {
 227                                 fprintf(stderr, "Error: Invalid error handler: %s\n",
 228                                                 optarg);
 229                                 exit(1);
 230                         }
 231                         conf.error_handler = optarg;
 232                         break;
 233
 234                 case 'I':
 235                         if (optarg[0] == '/') {
 236                                 fprintf(stderr, "Error: Invalid index page: %s\n",
 237                                                 optarg);
 238                                 exit(1);
 239                         }
 240                         uh_index_add(optarg);
 241                         break;
 242
 243                 case 'S':
 244                         conf.no_symlinks = 1;
 245                         break;
 246
 247                 case 'D':
 248                         conf.no_dirlists = 1;
 249                         break;
 250
 251                 case 'R':
 252                         conf.rfc1918_filter = 1;
 253                         break;
 254
 255                 case 'n':
 256                         conf.max_requests = atoi(optarg);
 257                         break;
 258
 259                 case 'x':
 260                         fixup_prefix(optarg);
 261                         conf.cgi_prefix = optarg;
 262                         break;
 263
 264                 case 'i':
 265                         port = strchr(optarg, '=');
 266                         if (optarg[0] != '.' || !port) {
 267                                 fprintf(stderr, "Error: Invalid interpreter: %s\n",
 268                                                 optarg);
 269                                 exit(1);
 270                         }
 271
 272                         *port++ = 0;
 273                         uh_interpreter_add(optarg, port);
 274                         break;
 275
 276                 case 't':
 277                         conf.script_timeout = atoi(optarg);
 278                         break;
 279
 280                 case 'T':
 281                         conf.network_timeout = atoi(optarg);
 282                         break;
 283
 284                 case 'k':
 285                         conf.http_keepalive = atoi(optarg);
 286                         break;
 287
 288                 case 'A':
 289                         conf.tcp_keepalive = atoi(optarg);
 290                         break;
 291
 292                 case 'f':
 293                         nofork = 1;
 294                         break;
 295
 296                 case 'd':
 297                         port = alloca(strlen(optarg) + 1);
 298                         if (!port)
 299                                 return -1;
 300
 301                         /* "decode" plus to space to retain compat */
 302                         for (opt = 0; optarg[opt]; opt++)
 303                                 if (optarg[opt] == '+')
 304                                         optarg[opt] = ' ';
 305
 306                         /* opt now contains strlen(optarg) -- no need to re-scan */
 307                         if (uh_urldecode(port, opt, optarg, opt) < 0) {
 308                                 fprintf(stderr, "uhttpd: invalid encoding\n");
 309                                 return -1;
 310                         }
 311
 312                         printf("%s", port);
 313                         break;
 314
 315                 /* basic auth realm */
 316                 case 'r':
 317                         conf.realm = optarg;
 318                         break;
 319
 320                 /* md5 crypt */
 321                 case 'm':
 322                         printf("%s\n", crypt(optarg, "$1$"));
 323                         return 0;
 324                         break;
 325
 326                 /* config file */
 327                 case 'c':
 328                         conf.file = optarg;
 329                         break;
 330
 331                 case 'C':
 332                         tls_crt = optarg;
 333                         break;
 334
 335                 case 'K':
 336                         tls_key = optarg;
 337                         break;
 338 #ifdef HAVE_LUA
 339                 case 'l':
 340                         conf.lua_prefix = optarg;
 341                         break;
 342
 343                 case 'L':
 344                         conf.lua_handler = optarg;
 345                         break;
 346 #endif
 347 #ifdef HAVE_UBUS
 348                 case 'u':
 349                         conf.ubus_prefix = optarg;
 350                         break;
 351
 352                 case 'U':
 353                         conf.ubus_socket = optarg;
 354                         break;
 355 #endif
 356                 default:
 357                         return usage(argv[0]);
 358                 }
 359         }
 360
 361         uh_config_parse();
 362
 363         if (!bound) {
 364                 fprintf(stderr, "Error: No sockets bound, unable to continue\n");
 365                 return 1;
 366         }
 367
 368         if (n_tls) {
 369                 if (!tls_crt || !tls_key) {
 370                         fprintf(stderr, "Please specify a certificate and "
 371                                         "a key file to enable SSL support\n");
 372                         return 1;
 373                 }
 374
 375 #ifdef HAVE_TLS
 376                 if (uh_tls_init(tls_key, tls_crt))
 377                     return 1;
 378 #else
 379                 fprintf(stderr, "Error: TLS support not compiled in.\n");
 380                 return 1;
 381 #endif
 382         }
 383
 384 #ifdef HAVE_LUA
 385         if (conf.lua_handler || conf.lua_prefix) {
 386                 if (!conf.lua_handler || !conf.lua_prefix) {
 387                         fprintf(stderr, "Need handler and prefix to enable Lua support\n");
 388                         return 1;
 389                 }
 390                 if (uh_plugin_init("uhttpd_lua.so"))
 391                         return 1;
 392         }
 393 #endif
 394 #ifdef HAVE_UBUS
 395         if (conf.ubus_prefix && uh_plugin_init("uhttpd_ubus.so"))
 396                 return 1;
 397 #endif
 398
 399         /* fork (if not disabled) */
 400         if (!nofork) {
 401                 switch (fork()) {
 402                 case -1:
 403                         perror("fork()");
 404                         exit(1);
 405
 406                 case 0:
 407                         /* daemon setup */
 408                         if (chdir("/"))
 409                                 perror("chdir()");
 410
 411                         cur_fd = open("/dev/null", O_WRONLY);
 412                         if (cur_fd > 0) {
 413                                 dup2(cur_fd, 0);
 414                                 dup2(cur_fd, 1);
 415                                 dup2(cur_fd, 2);
 416                         }
 417
 418                         break;
 419
 420                 default:
 421                         exit(0);
 422                 }
 423         }
 424
 425         return run_server();
 426 }